2012年10月11日星期四

Why Not Use a White Wall as Background

Identification photos are largely needed in
our daily life. When I was in university, I often take photos by myself and
develop them at print shop. It is simple to realize; just stand before a white
wall and ask your friend to press the shutter. Both time and money are saved.
And for product shots for a catalog, it looks better that way.

It seems extremely easy in theory while it
takes a lot of experience or a lot of slow and tedious work. First, you need to
understand what doesn’t work and why. You can’t put something in front of a
white wall, take the shot, and expect the background to be white. It won’t be.
Instead it will be some shade of gray. But it is possible to make this work
with just two lights – one for the subject and one for the background. If the
subject is very large, you will need at least two lights on the background. The
main thing is you have to pour a lot more light on the background than you do
on the subject.

Next, turn on your background light or
lights. You want it to fill the visible area of the background that will show
in the image. Take a picture again and look at the image in your LCD panel. If
your camera has something called highlight warnings (commonly “blinkies”), turn
that on. If the background is properly exposed, then the entire background will
be blinking and the subject will look well exposed. Once you get to that point,
you are done and you have a perfectly lit subject on a white background.

Although
you may face plenty of light and trial and error before accomplishing the same
thing, it is a worthwhile exercise to learn how to do it right before spending
more money. Just take a trial!